Process and apparatus for converting oils



March 7, 1933. G. EGLOFF PROCESS AND APPARATUS FOR CONVERTING OILS original Filed Oct.

31, 1921 2 Sheets-Sheet 1 usTav f g/ 1f March 7, 1933. G. EGLOFF PROCESS AND APPARATUS FOR CONVERTING OILS Original Filed Oct. 31. 1 21 2 Sheets-Sheet 2 llllllliillllx 1 m 2 passed through successive a more complete conversion of the oil in the Patented Mar. 7, 1933 UNITED s'r r S PATENT OFFICE eusrav EGLOFF, or cmcaeo, ILLINOIS, A'ssrcmoa- "r0 UNIVERSAL. 01L rnonucrs COMPANY, or CHICAGO, ILLINOIS, AcoaroaA'rIoN or SOUTH DAKOTA.

PROCESS AND APPARATUS FOR CONVERTING OILS Application filed October 31, 1921, Serial No. 511,902. Renewed lDecember 15.1928.

This invention relates to improvements in process and apparatus for converting oils and refers more particularly to .a process torelieve heavy oils from their lighter fractions.

Among-the salient objects of the invention areto provide a process in which the oil is stages of conversion'in-which, due to diflerential pressure and temperature conditions, fractions having somewhat different characteristics are re- 1) moved from the oil body; to provide a process in which the more refractory oils which are separated as reflux in the different zones of distillation or conversion are removed from the system; to provide a roc'ess in which the removal of these more re ractory oils permits separate stages as the presence of the refractory reflux retards the conversion when reintroduced to a zone of distillation; to provide an apparatus for carrying out the above described process.

In the drawings: i Figs. 1a and 16 how a side elevational v1ew of the apparatus, Fig. 1b bein'ga continuation of the apparatus shown in Fig. 1a.

' Describing more particularly the drawings, the raw oil is introduced through the inlet .line 1, controlled by a valve 2' and is charged by means of the pump 3 through the heating coils 4 mounted in a furnace 5. In this heat-- ing zone, the oil is subjected to cracking temperature and high pressure in order that a proper conversion of the oil body may be ob- It is a-well known fact that wheretained. the oil is subjected to a regulated pressure, a better quality of distillate may be obtained from the vapors generated therefrom after conversion or cracking has taken place. The

oil, after being heated in the furnace passes hrough the transfer line 6 to the initial con version zone. This initial conversion takes place in the expansion chamber 7, which is preferably ofthe construction shown, with an insulating refractory brick or cement 8 lining the interior shell of the chamber. The pur-. pose of this lining is to prevent loss of heat and at the same time, reduce the temperature to which the steel shell is subjected during the conversion reaction. During the conversion, the .oil is maintained under a high pressure and it is desirable where a steel shell or chamber of this character is subjected to a high pressure, that it shall not also have to undergo a high temperature. As is wellknown, high temperatures reduce to an extent the strength and capabilitiesof the still and for this reason, the conditions in the initial line 9 controlled by a valve 10 and afterbeing dephlegmated in the refluxing column 11, pass over through the line 12 controlledby a valve 13 to the water condenser 14. After being condensed, the vapors are collected as distilvlate in the receiving tank 15.

Theunvaporized portion ofthe oil in the inltial zone or conversion chamber 71 passes 'to. a second zone where further conversion takes place. The oil from the chamber 7 passes through the line 16 controlled by a pressure regulatlng valve .17 to the chamber v18. This chamber is somewhat similar to the primary chamber except that instead of being entirely lined with firebrick or a'refractory cement insulating material, the insulation or lining extends only about halfway up the sides-of the shell as shown by the dotted line .19. The chamber is mountedin a furnace 20 which is top fired as shownby means of burners 21. In this manner, the chamber may 7' be heated without danger of causinghot spots from carbon accumulation common to stills or other distillation apparatus where the heat is applied from below. The pressure in this chamberis'alsoreduced and withthis release. of pressure, there are generated vapors which pass off through the line22 in which is interposed a throttle valve 23; These vapors as, in the initial zone, are refluxed in the dephlegmator 24 and are subjected to a condensing actionxon passingthrough the line 25 which directs them to the condenser coil 26.

The vapors from the secondary zone aftercondensation are collected in the receiver 27. The unvaporized product passesfrom the secondary zone through the line 28 in which is a pressure regulating valve 29 similar to that shown at 17.

' is likewise top-fired in order to keep the oil at a proper temperature for conversion. The pressure on the oil body in this zone is lowered correspondingly so that the vapors pass up through the line 31, through the dephlegmator 32 and condenser 33, producing a third fractionation in the form of a distillate collected in the receiving tank 34. From the chamber 30, the unvaporized oil is passed through the line 35 controlled by a pressure regulating valve 36 to a final coking still 37 which is mounted above a furnace 38. In this final stage, the unvaporized oil is distilled until the residual product is a very heavy sludge or coky substance which is collected in the bottom of the still and is cleaned from time to time as the carbon accumulation becomes objectionable. The vaporous distillation products pass off through the line 39 in which is a valve 40, the pipe 39 connecting with a reflux line 41'.

The reflux condensate which is separated out in each of the dephlegmators 11,24 and 32, consists of an oil which is of a character that it is diflicult to crack and retards the conversion of any oil to which it is added. When this oil is isolated from the system and is treated separately, it has been found that more efl'icient operation may be obtained, and the cost of operation materially reduced due to the fact that it is unnecessary to maintain as high temperatures in each of the succeeding zones of the system in order to procure the same amount of conversion. For these reasons, the reflux oil from each of the dephlegmators may be drawn oil through the reflux lines 42, 43 and 44 respectively and directed through the by-pass lines 45, 46 and 47 to separate storage tanks or combined in the line 41, which is controlled by the valves 48, 49, 50 and 51 and thence directed to a separate apparatus for conversion. .The isolation of this oil greatly enhances the eflicient operation of the process and relieves the system of one of its most objectionable burdens as far as retreatment is concerned, namely, the removal of the refractory reflux condensates.

oils, consisting in passing the oil in a small coking still, the'temperatures may be regulated to conform with'the heat required to reduce the final product to coke. Thedistillate which passes over from the final or coking still-may be combined with the reflux or may be drawn ofi separately through the line Y 52 controlled by a valve 53.

I claim as my invention:

1. A process for converting hydrocarbon I5 stream through a furnace heated to a cracking temperature and thence through a series of vaporizing chambers serially connected and of progressively decreasing pres,- sures, while maintaining a pressure in excess of 500 pounds throughout said chambers, removing, dephlegmating and condensingithe generated vapors from each of said chambers, isolating the reflux condensate formed by dephlegmation from the separate vapor chambers, finally reducing the unvaporized product to coke in a coking still.

2. 1n an apparatus for converting hydrocarbon oils, the combination with a means for raising the oil to a crackingtemperature while maintaining a substantial pressure thereon, of a series of vaporizing chambers serially connected therewith, means for de-' phlegmating and condensing the vapors generated in the respective vaporizing chambers, means for maintaining decreasing pressures upon the successive vaporizing chambers, and a reflux header adapted to remove from the system the reflux condensate separated in the respective dephlegmators from the vapors 1'00 lgenerated in the separate vaporizing chamers.

3. A hydrocarbon oil cracking process which comprises flowing the oil through a restricted heating zone and heating the oil therein under superatmospheric pressure to a cracking temperature, discharging the heated oil into a reaction zone maintained under superatmospheric pressure wherein conversion of the oil occurs, separately removing unvaporized oil and evolved vapors from said reaction zone, dephlegmating said vapors and isolating the resultant reflux condensate from the process, passing said unvaporized oil through a series of pressure reduction zones maintained under successively lower pressures and effecting further vaporization of said unvaporized oil therein, reducing the unvaporized oil to coke in the last of said pressure reduction zones, condensing heavier fractions of the vapors evolved in said pressure reduction zones, and preventing return of the resultant condensates to said heating zone.

GUSTAV EGLOFF. 

